Quartz crystal resonator and method for manufacturing the same, and quartz crystal resonator unit and method for manufacturing the same

Abstract

A method for manufacturing a quartz crystal resonator that includes a quartz crystal blank having a vibrating portion including a center of a principal surface of the quartz crystal blank when viewed in plan from a direction normal to the principal surface and a peripheral portion adjacent to the vibrating portion, a pair of excitation electrodes disposed opposite to each other with the vibrating portion interposed therebetween, a pair of electrode pads disposed on the peripheral portion, and a pair of extended electrodes each extending from the vibrating portion to the peripheral portion to electrically connect one excitation electrode to a corresponding electrode pad, where the method includes conducting a first trimming of the vibrating portion and the peripheral portion; and conducting a second trimming of part of one of the excitation electrodes on the vibrating portion.

What is claimed is: 
     
       1. A quartz crystal resonator comprising:
 a quartz crystal blank having a vibrating portion including a center of a principal surface of the quartz crystal blank when viewed in plan from a direction normal to the principal surface and a peripheral portion adjacent to the vibrating portion; 
 a pair of excitation electrodes opposing each other with the vibrating portion interposed therebetween; 
 a pair of electrode pads on the peripheral portion; and 
 a pair of extended electrodes each extending from the vibrating portion to the peripheral portion to electrically connect one of the pair of excitation electrodes to a corresponding one of the pair of electrode pads, 
 wherein the pair of excitation electrodes includes a first excitation electrode and a second excitation electrode, 
 the first excitation electrode includes a first region having a thickness T 1  and a second region having a thickness T 2  larger than the thickness T 1 ; and 
 the second excitation electrode includes a third region having a thickness T 3  larger than the thickness T 2 . 
 
     
     
       2. The quartz crystal resonator according to  claim 1 , wherein the quartz crystal blank has a stepped portion at a boundary between the vibrating portion and the peripheral portion, and the extended electrodes each pass through the stepped portion. 
     
     
       3. A quartz crystal resonator unit comprising:
 the crystal resonator according to  claim 1 ; 
 a base member on which the quartz crystal resonator is mounted, with a side of the quartz crystal resonator having the second excitation electrode thereon facing the base member; and 
 a lid joined to the base member to seal the quartz crystal resonator therebetween. 
 
     
     
       4. The quartz crystal resonator unit according to  claim 3 , wherein the quartz crystal blank has a stepped portion at a boundary between the vibrating portion and the peripheral portion, and the extended electrodes each pass through the stepped portion.